Chain saw



June 20, 1944. A. N. BLUM 2,351,739

CHAIN SAW Filed Dec. 27, 1941 5 Sheets-Sheet 1 /f/g-i.

lJune 20, 1944. v A, N, BLUM 2,351,739

CHAIN SAW Filed Dec. 27, 1941 5 Sheets-Sheet 2 A. N. BLUM June 20, 1944.

CHAIN sAw yFiled Deo. 27, 1941 5 Sheets-Sheet 5 A. N. BLUM CHAIN SAW June 20, 1944.

Filed Dec. 27. 1941 5 Sheets-Sheet 4 Patented June 20, 1944 UNITED STATES [PATENT OFFICE CHAIN SAW Arthur N. Blum, Philadelphia, Pa.

Application December 27, 1941, Serial No. 424,651

24 Claims.

This application is a continuation in part of my copending application Serial Number 304,401 issued Sept. 22, 1942 as Pat. No. 2,296,240.

The aforesaid pending application discloses a chain saw of improved mechanical design and functional characteristics, and the present invention has for its primary object the provision of an improved and generally more effective 1ubricating means for chain saws of the character disclosed.

More specifically, an object of the invention is to provide a lubricating means which will more effectively and uniformly distribute oil from a suitable reservoir to the toothed chain and the surfaces of contact between the chain and the chain supporting and guiding elements.

Another object of the invention is to provide means for rendering the lubricating device, when desired, independent of gravity so that the lubri-` eating device may be uniformly effective irrespective of the position in which the saw may be manipulated, or the conditions under which the saw is required to operate.

Still another object is to provide a lubricating device which will utilize all of the available lubricant for lubricating purposes and to maximum advantage.

A further object ofthe invention is to provide a lubricating device which shall utilize capillary or semi-capillary action to advantage in directing the lubricant to the points where it is most needed for lubrication.

Still another object of the invention is to provide means fordirecting and regulating the feed of the lubricant to the opposite sides of the toothed chain and of the chain guide, and to provide means protecting the oil flowing to the guide rail and chain from contamination by sawdust.

Another object of the invention is to provide quick and effective means for cleaning the oil passages if they should become clogged by dirt in the oil itself, without necessity for disassembling.

A still further object of the invention is to provide a simple and inexpensive dual lubricating system providing selective gravity or pressure lubrication.

Further objects and features of the invention are hereinafter described and are illustrated in the attached drawings, in which:

Figure l is a fragmentary sectional view showing one end of a chain saw made in accordance with my invention and which is more fully illus Fin trated in my aforesaid copending application Serial Number 304,401;

Fig. 2 is a section on the line 2 2, Fig. 1;

Fig. 3 is a section on the line 3 3, Fig. 1; A

Fig. 4 is a view in perspective of that end of the guide rail for the toothed chain which is shown in Fig. l;

Fig. 5 is a view in perspective of one of the elements of the lubricating device forming the subject of the invention;v

Fig. 6 is a sectional view corresponding to Fig. 1 illustrating a modification within the scope of the invention;

Fig. 7 is a section' on the line 1 1, Fig. 6;

Fig. 8 is a section on the line 8 8, Fig. 6;

Fig. 9 isa view in perspective of the end of the saw shown in Fig. 6;

Fig. 10 is a section on the line ||J I0, Fig. 6;

Fig. 11 is a section on the line H I I, Fig. 6;

Fig. 12 is a fragmentary view in perspective of one of the elements of the structure shown in the immediately preceding figures;

Fig. ,13 is a view in perspective of one of the elements of the lubricating device shown in the immediately preceding figures;

Fig. 14 is a fragmentary elevational view corresponding to Figs. 1 and 6 illustrating still another modification within the scope of the invention;

Fig, 15 is a section on the line |5-l5, Fig. 14;

Fig. 16 is a section on the line |6 |6, Fig. 14,

and

Fig. 17 is an exploded view showing details of the construction shown in Figs. 14, 15 and 16.

Chain saws of the type with which the present invention is concerned are illustrated in my aforesaid Patent No. 2,296,240, and comprise essentially an endless toothed chain, a pair of sprockets supporting said chain, one of said sprockets being driven by suitable power means, and a guide for the chain which extends between the sprockets and supports and guides that portion of the chain which extends between the sprockets. l

In the attached drawings and with reference particularly to Figs. 1 to 5, inclusive, the toothed chain is designated by the reference numeral l, one of the said sprockets by the reference numeral 2, and the chain guide by the reference numeral 3. The guide 3 in the present instance is of plate form and is slotted at each longitudinal edge and as indicated at 4 for reception of tails 5 on alternate links 6 of the chain l, these tails fitting slidably within the slot 4 and functioning to retain the chain in alignment against the side thrusts to which it is unavoidably sub- Jected in operation. The inner edges of the links 1 which connect the links 6 nd a bearing upon the longitudinal edges of the guide plate 3 Yat opposite sides of the slot 4. The end of the guide plate 3 is clamped, by means hereinafter more specifically described, in a member 8, which vmember also provides a support for the sprocket 2 and for a tensioning device 9 by means of which the sprocket 2 may be adjusted longitudinally of the guide plate 3 so as to adjust the chain I to the required tension. The member 8 also carries a lubricant container which is connected with the guide plate 3 by means forming the subject of the present invention and hereinafter described.

The guide rail 3 is made up in the present instance of two outer plates I2 and I3 and an intermediate spacer plate |4, the three plates being solidly secured together by means of rivets I5. As illustrated in Fig. 4, the inner plate is of lesser width than the plates |12 and I3 so as t0 form the slots 4 in the longitudinal edges of the rail. Adjacent the end of the rail, the plates I2 and I3 are provided with registering apertures I6, and as indicated in broken lines in Fig. 1, the spacer plate is provided with a recess I1 which extends inwardly from the longitudinal edge in registration with the apertures' I6 of the plates I2 and I3. Corresponding apertures I8, I8 and recesses I9 are provided on the opposite side of the longitudinal center line of the rail, said sets of openings being symmetrically arranged with respect to said center line and to the adjoining y end of the rail, as illustrated. The function of this symmetrical arrangement will appear hereinafter.

The apertured end of the rail nts into a slot between two side portions or wings 2| and 22 of the member il,y and is clamped solidly between said wings by means of a screw 23 which passes through the apertures IG-I'I in the rail 3 and is threaded into the wing portion 22 of the member, the said wings being sufficiently flexible to constitute the jaws of the clamp actuated by the screw 23. It is to be noted that the opposite end of the rail 3 is solidly clamped 'in a second member or frame (not shown), and the two members in addition to the rail 3 are connected by means of a tie rod 24. An important function of the tie rod 24 is to act as a guard for the upper run of the chain I, and as a safety device in event of breakage of the chain while in operation.

The guide rail 3 is formed symmetrically with respect to the aforesaid longitudinal center line, and apertures corresponding to the apertures |6--II and |8|9 are provided also at the opposite end of the rail, so that as to these sets of apertures, the said rail is also symmetrical. This permits the adjustment of the rail to a reverse position in the assembly with respect to the said longitudinal center line, and also an end-to-end adjustment without in any way complicating or changing the means for securing the rail to the respective frame members. This ability for reversal of the position of the rail in the assembly is important, in that the wear caused by the moving chain upon the rail is not uniform throughout the slot, but is greater in localized areas, and the ability to adjust the rail in the assembly to the various positions described above provides for a longer useful life for this element.

As best illustrated in Fig. 3, the side member 22 of the member 8 is provided with a threaded aperture 23 which registers with the through Opening |8|8 0f the rail 2. Into this opening is threaded the terminal fitting 26 of a duct 21 which extends,` as shown in Fig. 2, to the reservoir chamber II of the member 8. The .duct 21 is provided with a suitable valve 28 so that the flow of lubricant from the chamber II through the duct may be regulated as required. A threaded port 2s is also provided in the side member 2| of the member 8 also in registration with the opening |8|8 of the guide rail. The opening 28 receives a hollow threaded plug 3|, see Figs. 3 and 5, this plug having at its inner -end a flattened cylindrical extension 32 which in assembly projects through the opening |8|3 in the rail. The rounded surfaces of the exten' sion 32 fit closely within the' opening |6|9,

whereby the extension actingas a dowel aids in immobilizing the end'of the guide rail inthe member 8, but the flattened surfaces of the extension 32 afford la clearance space between the extension and theiperipheral edges of the said opening, as shown in Fig. 3; The plug 3| has an axial bore 33; the outer end of Vwhich is threaded, as shown at 34 in Fig. 3, for reception of the outer threaded end 35 of a rod 36, this rod projecting through the bore 33 of the plug 3| and into the interior of the tting 26. The rod 3B is preferably of such diameter as to leave a space between its surface and the walls of the plug 3| and fitting 26.

When oil is allowedto pass through the duct 21, it comes in contact with theend of the rod 36, and by surface tension tends to follow the surface of the-rod whereby the oil is made to span the space between the inner end of the fixture 26 and the outer end of the extension 32 of the plug 3|. The oil passes through the spaces provided by the flattened surfaces of the extension 32 of the plug 3| to the opposite side of the rail. The oil thus accumulating on both sides of the rail passes over the outer surfaces of the latter to the recesses 2|a and 22a provided in wings 2| and 22 respectively to slot 4, and to the chain. Recesses 2|a and 22a, as shown, are open toward the rail edges and provide an effective means to protect the oil from contamination by sawdust and chips which are thrown on abundantly and forcibly bythe chain and sprocket against the terminal edge of the guide rail. Oil thus passing to the chain is distributed by the latter not only throughout the rail slots, but also to the chain-supporting sprockets, so that uniform effective lubrication of the chain and of the parts of the mechanism in frictional contact with the chain is afforded. It is to be noted also that the recess I9 in the plate I4 forms a direct passage between the apertures I8 and the slot 4 in the guide plate through which there is a direct flow of the lubricant to the slot. 'I'his lubricant is picked up and distributed throughout the slots by the tails 5 of the chain. The oil in recess I9 is, of course, also .protected from contamination and from clogging up the respec tive oil passages. Should this occur, however, as it might, due to the pounding of sawdust thrown off by centrifugal force of the sprocket, or due to dirt finding its way into the oil reservoir, or due to congealing in winter, theinvention provides a ready and quick means for cleaning these passages by removing rod 36 and inserting a flexible cleaning wire which may reach right into the valve 28, and through it, to the reservoir II.

In the aforedescribed embodiment of the inasuman vention, as well as in the embodiments hereinafter described, the fact that the lubricant is v conveyed in an enclosed passage or passages,`2|a and 22a, which form the terminal portions of what in effect is an uninterrupted enclosed channel from the source of lubricant to the side surfaces of the rail and insure an uninterrupted flow of the lubricant to the said railsurfaces, makes it possible to use the machine in any position without loss of lubrication. Furthermore, the disposition of the said passages at the outer sides of therail makes it possible to clean the passages conveniently from the outside without disassembling the machine and without removing the cutting chain from the rail.

Another novel improvement incident to terminating the lubricating passage outside of the chain supporting groove itself is thefact that the lubricant thereby has chance to spread by gravity over a wider surface of the rail than is encompassed by the width of the lubricating passage alone, whereby the lubricant before it reaches the chain is permitted to spread by gravity over an extended surface exposed when the saw is cutting to the random wiping action of the chips adhering to the side walls of the kerf,

thereby to preclude interruption of the lubricat-l ing function by localized clogging.

In the embodiment of my invention illustrated in Figs. 6 to 12, inclusive, the assembly in its major elements is substantially the same as that described above. In this case, however, the guide rail 4| is made of one piece of metal, the chain grooves 42 being milled or otherwise formed in the longitudinal edges. In this instance also, the rail 4| is clamped against one side portion 48 of the member 44 by means of a cover-plate 45 and screws 45 which are threaded into the side portion 43 and clamp the cover-plate 45 against the rail 4I.

As shown in Fig. l2, the rail 4| is recessed from the end edge, as indicated at 41, and in assembly this recess 41 receives a key element 48, to which,

` as best shown in Fig. 13, is secured by means of rivets 49 a U-shaped plate 5|. Preferably the side portions or wings of the :plate 5| are slightly spaced from the sides of the element 48 by means of washers 55. The end of the key element 48 which extends beyond the inner edges of the plate 5| `fis slightly offset, asindicated at 52, and this laterally offset portion of the key element ts closely into a slotted recess 53 formed in the sidev portion 43 of the member 44. 'I'hs interengagement of the key element and the slot definitely establishes the position of the element 48 in the member 44, and the closely fitting engagement between the element 48 and the recess 41 of the guide rail in turn establishes the positional relation between the rail and the member 44.

As shownv in Fig. 10, both the side member 43 and the clamping plate 45 are recessed, at 54 and 55 respectively, for reception of the plate 5|, and these recesses are of sufficient depth to provide for clearancebetween the outer surfaces of the plate and the inner opposed surfaces of the side member 43 and the clamping plate 45. Also, the recess 53 is suiiiciently deep so thatl the key element 48 will not interfere with the solid clamping of the guide rail 4| between the clamping surfaces oi' the side member 43 and clamping plate 45, as shown in Figs. and 11. The clamping screws 45, 45 pass through the element 48, and one through the side portions of the plate 5|, suitable apertures 55 and 51 being provided for passage of the said screws, as shown in Fig,V 13. It is to be noted that the curved outer end 58 of the plate 5| extends somewhat i beyond the inner terminal end 59 of the guide rail.'

The member 44, at the'inner end of the side member 48, is provided with a transverse boss 5|. The boss 5| is hollow, see Fig. 11, and the inner bore 52 of the boss registers with an aperture 53 in the-adjoining wing of the plate 5| and with a corresponding aperture 54 in the guide rail 4i. The outer end of the bore 52 communicates with a port 55 which extends diagonally through the wall of the boss and which is threaded for reception of a fitting 55 connected to a pipe 51 extending to the reservoir chamber 58 in the member 44. As in the previously described embodiment, the pipe 51 is provided with a valve 59 'to regulate the flow of lubricant from the chamber 58 to the bore 52. Threaded into the outer end of the bore and extending through the latter is a rod 1|, said rod being thus adjustable longitudinally in the bore and being held in adjusted position by a lock nut 12. The inner end of the rod engages the far wing 15a of the plate 5|, see Fig. l1, and by adjusting the rod, the flexible wing of the plate 5| may be adjusted transversely within the space between the guide rail 4| and the clamping plate 45 so as to regulate the relative spacing between the plate 5| and the opposed surfaces of the guide rail and the clamping plate 45. To facilitate this flexing of wing 15a, the U-shaped plate 5| is slotted as indicated at 99 in Fig. 13. As illustrated in Fig. 11, the element 48 is somewhat wider than the guide rail 4|, and this lprovides for slight clearance between the inner faces of the side wings of the plate 5| and the side faces of the rail, these clearances being indicated by the reference numeral 13. It should be noted that in this embodiment also, the oil is protected from contamination by the sawdust in its flow to the guide rail and chain The extended surface of the plate 5| serves to carry the lubricant which comes in contact therewith by way of the bore 52 outwardly to the toothed chain 14 which travels in the slots 42 of the guide rail 43, as previously described, it being noted by reference to Fig. 8 that the outer terminal edge portion 15 of the plate lies in close proximity to the chain. The lubricant is carried by capillary action through the narrow clearance spaces between the plate 5| and the rail 4|, and enters the chain groove 42. By action of the chain in the groove, the oil is thus dis-` tributed throughout the rail; and preferably a similar lubricating device is provided in the frame member at the opposite side of the rail. The rod 1| functions in the same manner as the rod 35 of the previously described embodiment, acting in the present instance as a bridge to conduct the oil past they one wing of the plate 5| and through the aperture 54 to the opposite wing to thereby insure more uniform lubrication at oppo site sides of the rail 4|.

In the embodiment illustrated in Figs. 6 to 13, and as shown particularly in Fig. 6, means is provided in conjunction with the reservoir 55 for creating pressure in the latter so as to force the lubricant through the duct 51 to the bore 53. This pressure means takes the form in the present instance of a hand pump 15 attached in the wall of the reservoir 58, as illustrated. When employing this pressure feed, it is essential that the reservoir be sealed,.except for the pipe 51,

and since it lmay be desirable under some circumstances to employ the conventional gravity feed for the lubrication, I provide a cap 11 having a. vent 18 which, when the cap is screwed tight, is sealed for pressure operation, and, when the cap is slightly loosened. is unsealed to permit the gravity feed. It will be apparent that the pressure feed is of particular advantage where the saw is used in positions precluding normal gravity feed of the lubricant from the reservoir, `and also whentemperature conditions are such as to prevent free ilow of the lubricant, and insures an adequate supply of lubricant to the running parts under all such conditions.

'I'he embodiment illustrated in Figs. 14 to 17, inclusive, is somewhat similar to that described above, in that the guide rail 19 and the frame member 8| are relatively positioned by means of a key 82 which ts a recess 83 in the side portion 84 -of the frame member and engages also in a slot 85 in the end of the guide rail. As in the previously described embodiment, screws 88 pass through apertures 81 in the key 82, and through apertures 88 in a clamping plate 89, said screws being threaded into tapped openings 9| in the side member 84 of the frame member so as to. clamp the guide plate solidly in position. In this case, the U-shaped plate I of the previously described embodiment is eliminated, and the in ner faces of the side member 84 and the clamping plate 89 are recessed at 92 and 93 respectively so as to afford a slight clearance between these faces and the opposite sides of the guide rail 19 by way of which the lubricant can be distributed to the guide rail and to the toothed chain free from contamination by sawdust. as in the previous embodiments. The member 84 has a passage .94 which is connected with a pipe 95 extending to the lubricant reservoir, and the inner end ofthe passage 94 registers with an aperture 98 in .the guide rail, this aperture 96 registering with the recess 93 in the clamping plate 89. A rod 91 extends through the passage 94 and aperture 98 and extends to the recess 93, as sho'wn in Fig. 16.

`From the aperture 98 'a channel 90 extends to the chain slot 80 in the rail 19 for passage of lubricant from the said aperture directly to the chain slot. If the channel 90, due to its position within the slot, should become clogged, the main lubricating passages 92 and 93, which are disposed sidewise of the median plane on the side surfaces of the rail will still maintain their lubricating function and are always accessible for cleaning from the side space adjoining the cutting chain so that such cleaning can be done without having to disassemble and to remove the cutting chain from the rail.

It will be noted further that the head 8| at the inner end of the side member 84 has a flange 98 which extends transversely across the inner end ping vand lying in close proximity to the proximate edge of the guide rail 19. Both outer ends of flange 98 are rounded inwardly at I 00 and Illll, producing a groove to retain the oil and conduct it against the guide rail, to save the oil being wasted.

'Ihe functional characteristics of this embodiment will be apparent from the foregoing descriptions, it being noted that in this case the surfaces of the recesses 92 and 93 and the closely opposed surfaces of the guide rail 19, as well as the oil groove |00, |02, |0I, function to distribute the lubricant to the desired areas when the guide rail is in horizontal position. The ange 98 acts also as an additional protection against sawdust thrown off by the sprocket.

l. In a chain saw having a guide rail and a cutting chain supported at the edge of said rail, a

source of lubrication external to said rail, a ductI from said source, and means to convey the lubricant from said duct to an outer surface of the rail, said means comprising an enclosed passage disposed at the outer side of the rail accessible for cleaning without removal of the cutting chain and forming a substantiallyl uninterrupted enclosed channel from the said duct to the said outer surface whereby the lubricant before it reaches the chain is permitted to spread by gravity over an extended surface exposed when the saw is cutting to the random wiping action of the chips'A in the kerf thereby to preclude interruption of the lubricating function by localized clogging.

2. In a chain saw having a guide rail and a cutting chain supported at thev edge of said rail, a source of lubrication external to said rail, an enclosed passage at the side of the rail, and a duct connecting thepassage with said source, said passage opening directly to an exposed surface of the saw structure leading to the chain and being accessible for cleaning without removal of the cutting chain and forming a substantially uninterrupted enclosed channel from said duct to the said surface whereby the lubricant before it reaches the chain is permitted to spread by gravity over an extended surface' exposed when the saw is cutting to the random wiping action of the chips in the kerf thereby to preclude interruption of the lubricating function by localized clogging.

3. In a chain saw having al guide rail for the chain, a lubricant duct terminating at one side of said rail, an aperture in the rail, and a rod-like element in the duct extending to said aperture so as to provide a path for lubricant between the mouth of the duct and said aperture.

4. In a chain saw having a guide rail and a cutting chain supported at the edge of said. rail. a source of lubrication external to said raiLan enclosed passage at one side of the rail, said passage opening toward an edge of the rail so as to afford access to the passage for cleaning without removal of the cutting chain, a corresponding passage at the other side of the rail, an aperture in said rail connecting said passages, and a duct extending from said source to said aperture, said passages opening directly to the respective outer side surfaces of the rail and forming a substantially uninterrupted enclosed channel from said duct to the said surface whereby the lubricant before it reaches the chain is permitted to spread by the gravity over an extended surface exposed when the saw is cutting to the random wiping action of the chips in the kerf thereby to preclude interruption oi the lubricating function by localized clogging.

5. In a chain saw having a guide rail and a cutting chain supported at the edge of said rail, a source of lubrication external to said rail, a duct from said source extending to one outer side surface of the rail, said rail having an aperture connecting said surface with the opposite outer side surface and communicating with said duct, and means in contact with and providing an enclosed passage at least at one of said outer side surfaces to convey the lubricant to the chain supporting rail edge, said enclosed passage opening toward an edge of the rail so as to aiord access to the passage for cleaning.

6. In a chain saw having a guide rail and a source of lubrication external to said rail, a duct from said source, and means extending uninterrupted1y from the said duct to the opposite side surfaces of the rail and providing a continuous track for lubricant from said duct to said surfaces, said means including an aperture in the rail communicating with the duct, and an enclosed passage at each side of the rail also communicating with said aperture and leading to the chain-supporting edge of the rail.

7. A chain saw having a guide rail for the chain, a head member, and means for clamping. the rail in the member, said means comprising clamping elements on the member for engagement respectively with opposite side faces of said rail, a source of lubricant, said elements having aligned apertures, a duct extending from said source to one of said apertures, a hollow plug secured in the other of said apertures, an aperture in said rail aligned with the apertures in said clamping elements, said plug having a dowel-like extension projecting into said rail aperture and terminating short of the end of said duct, and an element in said duct projecting from the latter into the interior of said plug and forming a path for lubricant from the duct to the surfaces of said plug for distribution from said surfaces to the surfaces of said rail.

8. A chain saw having a chain-supporting rail, and a guide slot in said rail, a head member, and means for clamping the rail in the member, said means comprising clamping elements on the member ,for engagement respectively with opposite side faces of said rail, said elements having aligned apertures, a source of lubricant, a duct extending from said source to one of said apertures, a hollow plug secured in the other of said apertures, an aperture in said rail aligned with the apertures in said clamping elements, said plug having a dowel-like extension projecting into said rail aperture and terminating short of the end of said duct, and an element in said duct projecting from the latter into the interiorof said plug and forming a path for lubricant from the duct to the surfaces of said plug for distribution from said surfaces to the surfaces of said rail, said rail having a channel extending from said aperture to the guide slot.

9. A chain saw having a guide rail for the chain, a head member, an aperture in said rail, clamping elements on the head engaging the opposite side faces of the rail in the area surrounding said aperture, the clamping faces of said elements being recessed immediately opposite said aperture, said clamping elements each having an aperture in alignment with said rail aperture, a source of lubricant, a duct extending from said source to the aperture in one of said elements, a

ho1low plug in the aperture of said other element and comprising an end portion projecting into the aperture in said rail and terminating short of the end of said duct, and a rod removably mounted in said plug and extending through the hollow interior thereof and into the end of said duct and forming a path for lubricant from the duct to the surfaces of said plug for distribution to said rail through the aperture in the latter.

10. A chain saw having a guide rail for the chain, a head member, means for clamping one side face of said rail against a face of said member, said means comprising a` clamping plate secured to said member and engaging the opposite face of said rail, the opposed faces of said member and clamping plate each having a recess extending inwardly from one edge thereof and said recesses being separated by said rail, an aperture extending into the recess in said member, a source of lubricant, a duct extending from said source to said aperture, said rail having an aperture, and

means extending from the duct and through the said rail aperture into engagement with the wall of the recess in said clamping plate and providing a path for lubricant from said duct to the lastnamed recess.

1l. A chain saw having a guide rail for the chain, a head member, means for clamping one side face of the rail against a face of said member, said means comprising a clamping plate se- I cured to said member and engaging the opposite face of the rail, the said face of the member having a recess, a key fitting the said recess and of greater thickness than the depth of the latter, said rail having in the terminal end thereof a recess for reception of said key whereby to establish the relative positions of said member and rail, clamping bolts intersecting said clamping plate and key, registering' apertures in the member and in said rail at one side of the key-receiving recess in the latter, a source of lubricant, a duct extending from the said source to the aperture in said member, and recesses in the clamping faces of said member and clamping plate ernbracing the area of said apertures, said recesses extending to adjoining edges of said member and plate and providing channels for the passage of the lubricant to an outer edge of said rail.

12. In a chain saw having a guide rail for the chain, a head member, said member havingl opposed clamping faces engaging opposite faces of the rail, a shallow recess in each of said clamping faces, an aperture in said rail communicating with said recesses, an opening in said member terminating in the bottom of one of said recesses in alignment with the said aperture in the rail, a source of lubricant, a duct extending from the source to said opening, and a rod extendingl from the mouth of the duct and through the rail aperture to the bottom of the opposite recess and affording a path for lubricant to the latter.

13. A chain saw having a rail with guide slots in the longitudinal edges thereof for the chain, a head member, said member having opposed clamping faces engaging opposite faces of the rail, a shallow recess in each of said clamping faces, an aperture in said rail communicating with said recesses, an opening in said member terminating in the bottom of one of said recesses in alignment with the said aperture in the rail, a source of lubricant, a duct extending from the source to said opening, a rod extending from the mouth of the duct and through the rail aperture to the bottom of the opposite recess and affording a path for lubricant to the latter, and a channel in said rail.l extending from the said aperture to the guide s o 14. In a chain saw having a guide rail for the chain, a head member, said member having opposed clamping faces engaging opposite faces of the rail, a recess in each of said clamping faces, an aperture in said rail communicating with said recesses, an opening in said member terminating in one of said recesses in alignment with the said aperture in the rail, a source of lubricant, a duct extending from the source to said opening, a plate element mounted in each of said recesses, the plate element in the recess which communicates with the said duct being separated by a narrow space from the bottom of the recess and from the opposed face of the rai1 and having an aperture in alignment with the rail aperture and with the opening in said member, the plate element in the other of the recesses being narrowly spaced from the adjoining face of the rail, and a rod element projecting from the mouth of the duct and through said opening and apertures to the lastposed clamping faces engagingopposite faces of the rail, a recess in each of said clamping faces, an aperture in said rail communicating with said recesses, an opening in said member 4terminating in one of said recesses in alignment with the said aperture in the rail, a source of lubricant, a duct extending from the source to said opening, a, plate element mounted in each of said recesses,y the plate element in the recess which communicates with the said duct being separated by a narrow space from the bottom of the recess and from the opposed face of the rail and having an aperture in alignment with the rail aperture andwith the opening in said member, the plate element in the other of the recesses being narrowly spaced from the adjoining face of the rail, and a rod element mounted in said duct and projecting from the latter and through said opening and apertures into engagement with the last-named plate. said rod being longitudinally adjustable and constituting thereby a means for positioning the said plate in the recess with respect to the surface of the rail.'

16. In a chain saw having a guide rail for the chain, a head member, said member having opposed clamping faces adapted to receive therebetween one end of the rail for clamping engagement with opposite faces of the latter, a recess in each of said clamping faces, an`aperture in said rail communicating with the recesses, an opening in said member terminating in one of said recesses in alignment with said aperture in the rail, a source of lubricant, a duct extending from the source to said opening, a U-shaped plate embracing the terminal end oi.' the rail and extending into said recesses, and means for supporting the wings of said plate in narrowly spaced relation to the side faces of the rail, that one of the wings adjoining the saidopening having an aperture in alignment with said opening and with the aperture in the rail, and means projecting from the mouth of said duct and through the said opening and apertures to the other wing of said plate and affording a path for lubricant to said wing.

17. In a chain saw having a guide rai1 for the chain, a head member, said member having opposed clamping faces adapted to receive therebetween one end of the rail for clamping engagement with opposite faces of the latter, a recess in each of said clamping faces, an aperture in said rail communicating with said recesses, an opening in said member terminating in onev of said recesses in alignment with said aperture in the rail, a source of lubricant, a duct extending from the source tosaid opening, a key element seated in recesses in the end of the rail and in one of said clamping faces and positively interlocking the rail with said member, and a U-shaped plate lelement attached to said key and extending into the first-named recesses in said clamping faces, said plate element lying in narrowly spaced relation to the faces of the rail and having an aperture in its arm nearest to and in alignment with the said duct Iopening and rail aperture, and a removable rod element projecting from the duct through said opening and apertures to the plate member at the opposite side of the rail.

18. In a chain saw having a guide rail for the chain, a head member. said member having opposed clamping faces for clamping engagement with opposite faces of the rail, a recess in each of said clamping faces, an aperture in said rail communicating withv said recesses, an opening in said member terminating in one of said recesses in alignment with the said aperture in the rail, a source of lubricant, a duct extending from the source to said opening, a key element interlocking with the rail and said member so as to positively fix the relative positions thereof, and 1ubricant-distributing means carried by `said key and extending into the said recesses.

19. In a chain saw having a guide rail for the chain, a member having a lubricant reservoir normally above the guide rail, a duct for conducting lubricant from the reservoir to the rail, means providing an enclosed passage for conducting the lubricant over the sides of the rail to the chain-supporting edge of the latter, a vent in the wall of said reservoir for admitting air during gravity flow of the lubricant through the duct, means for selectively opening and closing said vent, and means o n said member for applying air pressure to the interior oi' said reservoir for forced feed of lubricant through the duct.

20. In a chain saw having a guide rail for the chain, a member attached to one end of the rail and having a reservoir for lubricant, said member having opposed clamping faces engaging opposite faces of the rail, a flange projecting from one of said faces and forming a lubricant retaining and distributing groove at the end of the rail, and means for conducting lubricant from the reservoir to the rail.

21. A chain saw having a guide rail for the chain, a source of lubricant external to said rail, a member supporting the rail to which one end of the guide rail is attached, said member providing an enclosed recess for conveying the lubricant to a chain-supporting rail edge, an element clamped against the side surface of said rail and having also an enclosed recess for conducting the lubricant to the chain-supporting edges of said rail, and an aperture communicating with the recess last named and connecting the recess with said source of lubricant.

22. A chain saw having a guide rail for the chain, a source of lubricant external to said rail, a supporting member to which one end of the guide rail is attached, means for clamping one side face of said rail against a -face of said member, said means comprising a clamping plate engaging the opposite side of the rail, the opposed faces of the member and plate in contact with the rail having recesses which together with said outer side faces of the rail form enclosed passages to conduct the lubricant to the chain-supporting edges of the guide rail so that said passages remain accessible for cleaning from the outside of the rail without requiring the removal of said chain from the rail, said rail having an aperture in communication with said recesses, and means for connecting the recesses with said source.

23. A chain saw having a guide rail for the chain, a source of lubricant, a supporting memone side face of said rail against a face of said member, said means comprising a clamping plate engaging the opposite side of the rail, the opposed faces of the member and plate in contact with the rail having enclosed recesses to conduct the lubricant to the cham-supporting edges of the guide rail, said rail having an aperture in communication with said recesses, means for connecting the said recess in the member with said source of lubricant, an aperture in said plate affording access to the recesses in said plate and member and to the said connecting means to said source for cleaning purposes, and detachable means for normally closing the aperture in said plate.

ARTHUR N. BLUM. 

